Mating behavior of the lemon shark, Negaprion brevirostris (Carcharhiniformes: Carcharhinidae), as revealed by citizen science in the Equatorial Atlantic Ocean / Comportamiento de apareamiento del tiburón limón Negaprion brevirostris (Carcharhiniformes: Carcharhinidae), revelado por la ciencia ciudadana en el Océano Atlántico Ecuatorial

Introduction: Knowledge on the mating behavior and habitat requirements of large sharks, including the lemon shark, Negaprion brevirostris, is scarce, hampering conservation efforts. Objective: To describe an area in the Equatorial Atlantic used as a mating ground by N. brevirostris, as well as part of the species pre-copulatory behaviors based on citizen reports. Methods: Between 2004 and 2019, recreational divers, dive guides and rangers from the Marine Protected Area (MPA) in Fernando de Noronha Archipelago (FEN) recorded courtship behaviour, females with mating scars, pregnant females, and adult males. Results: N. brevirostris was recorded mating in shallow waters (0.5-2 m deep) during the austral summer (December to March). A specific location in the MPA, Buraco da Raquel lagoon, was the main aggregation and mating site for adult N. brevirostris in FEN. Conclusions: Citizen science records allowed the identification of shallow waters as key sites for the reproduction of this shark in FEN. Results highlight the potential of citizen science contributions to knowledge of sharks in nature and show MPAs as essential for habitat conservation of sharks with decreasing populations along the Brazilian coast, such as N. brevirostris. We present management recommendations to protect N. brevirostris there and elsewhere.

Introducción: El conocimiento sobre el comportamiento reproductivo y requisitos de hábitat de apareamiento de los tiburones grandes, incluido el tiburón limón, Negaprion brevirostris, es escaso, lo que dificulta los esfuerzos de conservación. Objetivo: Describir un área en el Océano Atlántico ecuatorial utilizada como zona de apareamiento y las interacciones precopulatorias del tiburón limón con base en informes proporcionados por ciencia ciudadana. Métodos: Buzos recreativos, guías de buceo y guardaparques del Área Marina Protegida (AMP) en el archipiélago Fernando de Noronha (FEN) llevaron registros de comportamientos de cortejo, hembras con cicatrices de apareamiento, hembras preñadas y machos adultos, entre 2004 y 2019. Resultados: Las aguas poco profundas entre 0.5 y 2 m de profundidad son utilizadas como áreas de apareamiento por N. brevirostris durante el verano austral (diciembre a marzo). Un lugar específico, dentro del AMP (laguna de Buraco da Raquel), fue identificado como el principal sitio de agregación y apareamiento de adultos de N. brevirostris en FEN. Conclusiones: Registros de ciencia ciudadana permitieron identificar aguas poco profundas como sitios clave para la reproducción de este tiburón en FEN. Los resultados resaltan el potencial de las contribuciones de la ciencia ciudadana al conocimiento de los tiburones en la naturaleza y muestran que las AMP son esenciales para la conservación del hábitat de tiburones con poblaciones decrecientes a lo largo de la costa brasileña, como N. brevirostris. Presentamos recomendaciones de gestión para proteger a N. Brevirostri, allí y en otros lugares.

Morfología microestructural dérmica en juveniles de dos especies hermanas de tiburón pala, Sphyrna tiburo y S. vespertina / Dermal microstructural morphology in juveniles of two sister species of bonnethead shark, Sphyrna tiburo and S. vespertina

RESUMEN: Los dentículos dérmicos son estructuras dermales presentes en el grupo de los condrictios, tienen un papel muy importante en su biología y se les ha utilizado como un carácter taxonómico que permiten reconocer grupos o especies. Por lo que en el presente trabajo se compara la morfología dermal de los juveniles de dos especies de tiburones pala, Sphyrna tiburo y S. vespertina, cuyo origen evolutivo está emparentado con el cierre del istmo centroaméricano. Para ello se obtuvieron muestras dermales (1 cm2) de tres regiones corporales y se procesaron para obtener imágenes de alta resolución por medio de Microscopia electrónica de barrido (MEB). Los dentículos de ambas especies tienen un patrón morfológico común, con variaciones en la longitud de las prolongaciones de las crestas, área libre y superposición de los dentículos, y grado de notoriedad de la ornamentación microestructural.

SUMMARY: The dermal denticles are dermal structures present in the group of chondrichthyans, they have a very important role in their biology and they have been used as a taxonomic character that allows to recognize groups or species. Therefore, in the present work, the dermal morphology of the juveniles of two species of shovel sharks, Sphyrna tiburo and S. vespertina, whose evolutionary origin is related to the closure of the Central American isthmus, is compared. For this, dermal samples (1 cm2) from three body regions were obtained and processed to obtain high resolution images by means of scanning electron microscopy (SEM). The denticles of both species have a common morphological pattern, with variations in the length of the ridge extensions, free area and overlapping of the denticles, and the degree of notoriety of the microstructural ornamentation.

Fatores associados aos óbitos e ataques de tubarão: um estudo transversal / Factors associated with shark attacks and deaths: a crosssectional study / Factores asociados con las muertes y los ataques de tiburones: estudio transversal

OBJETIVO: avaliar os fatores associados aos óbitos e ataques de tubarão no Brasil. MÉTODO: trata-se de um estudo transversal, quantitativo, realizado mediante acesso virtual ao website do Global Shark Attack File. A análise foi realizada no programa R, a partir de estatística descritiva e dos testes de Qui-quadrado de Pearson e Teste Exato de Fisher. RESULTADOS: ocorreram 86 ataques, dos quais 26 (30,2%) resultaram em óbito. Foi encontrada associação entre a ocorrência de ataque com o ano, estado, região, dia da semana, turno e espécie do tubarão, além da faixa etária, sexo da vítima e local do corpo acometido. Nenhuma variável apresentou associação com o óbito. O estado de Pernambuco computou o maior número de ataques (83,7%) e óbitos (96,2%). CONCLUSÃO: os ataques de tubarão estiveram associados com nove variáveis: três de caracterização da vítima e seis do perfil do acidente. Os óbitos não apresentaram associação significativa. Pernambuco sobressaiu como estado com maior ocorrência de ataque e óbitos.

OBJECTIVE: to evaluate the factors associated with shark attacks and deaths in Brazil. METHOD: this is a cross-sectional and quantitative study, carried out through virtual access to the Global Shark Attack File website. The analysis was performed in the R program, using descriptive statistics and the Pearson's chi-square and Fisher's exact tests. RESULTS: there were 86 attacks, of which 26 (30.2%) resulted in deaths. An association was found between occurrence of the attacks and year, state, region, day of the week, shift and shark species, in addition to the victim's age group and gender and to the part of the body affected. No variable was associated with death as outcome. The state of Pernambuco accounted for the largest number of attacks (83.7%) and deaths (96.2%). CONCLUSION: shark attacks were associated with nine variables: three related to the victim's characterization and six to the profile of the accident. The deaths did not present a significant association. Pernambuco stood out as the state with the highest occurrence of attacks and deaths.

OBJETIVO: evaluar los factores asociados con las muertes y los ataques de tiburones en Brasil. MÉTODO: se trata de un estudio transversal, cuantitativo, realizado a través del acceso virtual al sitio web Global Shark Attack File. El análisis se realizó mediante el programa R, utilizando estadística descriptiva y chi-cuadrado de Pearson y prueba exacta de Fisher. RESULTADOS: hubo 86 ataques, de los cuales 26 (30,2%) resultaron en muerte. Se encontró que hay asociación entre el ataque y el año, estado, región, día de la semana, turno y especie de tiburón, además del rango etario, sexo de la víctima y parte del cuerpo afectada. Ninguna variable se asoció con la muerte. El estado de Pernambuco tuvo el mayor número de ataques (83,7%) y muertes (96,2%). CONCLUSIÓN: los ataques de tiburones se asociaron con nueve variables: tres de la caracterización de la víctima y seis del perfil del accidente. Las muertes no mostraron una asociación significativa. Pernambuco se destacó como el estado con mayor número de ataques y muertes.

Patient survival and limb salvage after shark attack with major vascular injury: A case report / 中华创伤杂志(英文版)

Shark attacks are rare unique pathological processes. Some of them represent devastating injuries with a high morbidity and significant mortality. Related published articles are limited. The increased human interaction within the environment of sharks is the cause of rising incidence of such attacks. This study reported a case of level 4 shark injuries (shark-induced trauma scale) in a 33-year-old male patient, who presented with an extensive injury of the right lower limb with the characteristic features of shark bite. At admission the patient was in a state of shock with profuse bleeding that was controlled by tourniquet. The patient was resuscitated according to the advanced trauma life support. Clinical examination showed hard signs of vascular injury with absent pedal pulse, associated neurological deficits and severance at the knee joint. Prompt vascular intervention after resuscitation was performed to manage the major vascular injuries, together with proper washout and debridement of all the necrotic tissues under strong antibiotic coverage to prevent infection. After that, the patient underwent sequenced plastic, orthopedic, and neurological interventions. Strict follow-up was conducted, which showed that the patient was saved and achieved a functioning limb. This study aims to highlight the management of level 4 shark injuries, which are considered serious and challenging with a high fatality rate and a great risk of amputation due to the associated major vascular injuries. Immediate well organized management plan is crucial. Prompt resuscitation and surgical intervention by a highly-skilled medical team are required to improve the chance of patient survival and limb salvage.

Simple synthesis of photoluminescent carbon dots from a marine polysaccharide found in shark cartilage

BACKGROUND: For more than a decade, water-soluble, eco-friendly, biocompatible, and low-toxicity fluorescent nanomaterials have received considerable attention for their numerous in vivo and in vitro applications in biomedical imaging, disease diagnostics, and environmental monitoring. Owing to their tunable photoluminescence properties, carbon-based luminescent nanomaterials have shown great potential in bioimaging, photocatalysis, and biosensing among other applications. RESULTS: Marine environments provide excellent resources for the fabrication of these nanomaterials, because many marine organisms contain interesting trigger organic compounds that can be used as precursors. Herein, we synthesize multi-color emissive carbon dots (CDs) with an intrinsic photoluminescence quantum yield of 20.46%. These nanostructures were achieved through the one-step hydrothermal treatment of marine polysaccharide chondroitin sulfate, obtained from shark cartilage, in aqueous solution. CONCLUSIONS: We successfully demonstrate the low toxicity of our marine resource-derived CDs in zebrafish, and provide an initial assessment of their possible use as a bioimaging agent. Notably, the newly synthesized CDs localize in the intestines of zebrafish larvae, thereby indicating their biocompatibility and potential use as in vivo dyes.

Diafanización dental de cuatro especies de seláceos (Carcharhinus leucas, Galeocerdo cuvier, Rhizoprionodon longurio y Sphyrna sp) / Dental diaphonization of four salaceos species (Carcharhinus leucas, Galeocerdo Cuvier, Rhizoprionodon longurio and Sphyrna sp)

El estudio morfológico de la dentadura de chondrichthyes representa un carácter taxonómico importante empleado para la clasificación e identificación de diferentes especies. Se diafanizaron dientes de cuatro especies distintas de selacimorfos (Carcharhinus leucas, Galeocerdo cuvier, Rhizoprionodon longurio y Sphyrna sp.) con la finalidad de estandarizar una técnica dental para su transparentación. Estandarizando la técnica de Okumura-Aprile aplicada para la diafanización dental de humanos, se obtuvo una diafanización óptima en las cuatro especies en tratamiento con HCl al 7 % donde se podía observar con claridad la cámara pulpar, por lo que podemos concluir que la técnica de Okumura-Aprile es eficiente en la diafanización dental de tiburones.

The morphological study of the chondrichthyes teeth represents an important taxonomic characteristic used for the classification and identification of different species. The teeth of four different species of selacimorphs (Carcharhinus leucas, Galeocerdo cuvier, Rhizoprionodon longurio and Sphyrna sp.) were diaphonized in order to standardize a dental technique for their transparency. By standardizing the Okumura-Aprile technique applied for the dental diaphonization of humans, an optimal diaphonization was obtained in the four species treated with 7 % HCl where the pulp chamber was clearly observed. Therefore, we may conclude that the OkumuraAprile technique is efficient in shark dental diaphonization.

Progress in shark single-domain antibody / 生物工程学报

Monoclonal antibody (mAb) is an important biological macromolecule and widely used in immune detection, in vitro diagnostics, and drug discovery. However, the inherent properties of mAb restrict its further development, such as high molecular weight and complex structure. Therefore, there is an urgent need to develop alternatives for mAb. Various types of miniaturized antibodies have been developed, among which the variable domain of immunoglobulin new antigen receptor (VNAR) is very attractive. The shark single-domain antibody, also known as shark VNAR, is an antigen-binding domain obtained by genetic engineering technology based on the immunoglobulin new antigen receptor (IgNAR) that naturally exists in selachimorpha. It has a molecular weight of 12 kDa, which is the smallest antigen-binding domain found in the known vertebrates at present. Compared with mAb, the shark VNAR exhibits various superiorities, such as low molecular weight, high affinity, tolerance to the harsh environment, good water solubility, strong tissue penetration, and recognition of the hidden epitopes. It has attracted wide attention in the fields of immunochemical reagents and drug discovery. In this review, various aspects of shark VNAR are elaborated, including the structural and functional characteristics, generating and humanization techniques, affinity maturation strategies, application fields, advantages and disadvantages, and prospects.

Parturition time for the Blacktip shark, Carcharhinus limbatus (Carcharhiniformes: Carcharhinidae), in Southwestern Atlantic

The determination of the period of parturition and identification of nursery areas are fundamental for the management and conservation of a fishing resource. Through combination of monthly abundance, length measurements, and development time of embryos we inferred about parturition time of the Blacktip sharks, Carcharhinus limbatus, from Southwestern Atlantic. Specimens of C. limbatus were caught from 2002 and 2008 by artisanal fleets from three different locations along the Brazilian coast using gillnets (mesh width ranging between 30 and 120 mm between opposite knots and operating from 9 to 120 m in depth), handlines (19 to 140 m depth) and longlines (6 to 90 m depth). Through a comparative analysis of fisheries landing data collected, we have verified neonatal (< 90 cm) catch peaks at specific times of the year in different locations and, matching with birth prediction of embryos, propose that C. limbatuspresents a well-defined parturition time in late spring-early summer in Southwestern Atlantic. Moreover, we indicate supposed nursery grounds for the species along the Brazilian coast. This information will be crucial for stock assessments of the species and may serve as a basis for determining fisheries management measures.(AU)

A determinação do período de parto e identificação de áreas de berçário são fundamentais para o manejo e conservação da espécie. Através da combinação de abundância mensal, comprimentos e tempo de desenvolvimento de embriões nós inferimos sobre a época de parto do tubarão galha preta, Carcharhinus limbatus, no Sudoeste Atlântico. Espécimes de C. limbatus foram capturados entre 2002 e 2008 por frotas artesanais de três locais diferentes ao longo da costa brasileira usando redes de emalhar (largura de malha variando entre 30 e 120 mm entre nós opostos e operando de 9 a 120 m de profundidade), linhas de mão (19 a 140 m de profundidade) e espinhel (6 a 90 m de profundidade). Através de análise comparativa de dados de desembarque pesqueiro, verificamos picos de captura de neonatos (< 90 cm) em períodos específicos do ano em diferentes localidades e, combinando com a previsão de nascimento de embriões, propomos que C. limbatus apresenta um período de parto bem definido no final da primavera e início do verão no Sudoeste do Atlântico. Além disto, nós indicamos prováveis áreas de berçário ao longo da costa brasileira. Estas informações serão cruciais para avaliações de estoque da espécie e poderão servir de base para determinação de medidas de manejo de pescarias.(AU)

Mercury concentration in shark meat from traditional markets of Gyeongsangbuk-do, South Korea

Shark liver oil consumption decreases contractility in EDL muscle of trained rats / O consumo de óleo de fígado de tubarão reduz a contratilidade do músculo EDL em ratos treinados / El consumo de aceite de hígado de tiburón reduce la contractilidad del músculo EDL en ratones entrenados

Abstract Introduction: Professional and recreational athletes make daily use of nutritional supplements to improve physical performance. Polyunsaturated fatty acids (PUFAs) have been used in this sense. N-3 PUFA, particularly eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids are involved in important physiological functions and the benefits of supplementation are demonstrated in several types of users. Shark liver oil (SLO) is a natural source of n-3 PUFA. Objective: To evaluate the effect of supplementation with SLO on contractility of skeletal muscles with different metabolic characteristics, soleus and extensor digitorum longus (EDL) from rats submitted to eight weeks of interval training of progressive intensity on a motorized treadmill. In the supplemented group, animals were supplemented with SLO (1 g/kg) five times a week for eight weeks. Method: Contractile parameters as maximum isometric twitch force (Tmax), maximum speed of force development (+dF/dt), maximum speed of force decrease (-dF/dt), maximum tetanic force (Fmax) and resistance to fatigue were analyzed in isolated muscle. Results: Compared to the control group, EDL muscles from the supplemented group reduced Tmax at the first (10.82 ± 0.89 vs 14.30 ± 0.67 mN/mm2. p < 0.01) and second minutes of experimentation (9.85 ± 0.63 vs 13.12 ± 0.70 mN/mm2. p < 0.01). However, it increased resistance to fatigue (22.80 ± 0.97 vs 18.60 ± 0.51 seconds. p = 0.005). Conclusion: No difference was observed in the soleus muscle.

Resumo Introdução: Atletas profissionais e recreativos utilizam suplementos nutricionais diariamente para melhorar a performance física. Os ácidos graxos poliinsaturados (PUFA) têm sido usados nesse sentido. Os n-3 PUFA, particularmente os ácidos eicosapentaenoicos (EPA) e docosaexaenoico (DHA), são relacionados com importantes funções fisiológicas e os benefícios da suplementação são demonstrados em diversas populações. O óleo de fígado de tubarão (OFT) é fonte natural de n-3 PUFA. Objetivo: Avaliar o efeito da suplementação com OFT na contratilidade de músculos esqueléticos com diferentes características metabólicas, sóleo e extensor longo de dedos (EDL) de ratos submetidos a oito semanas de treinamento intervalado de intensidade progressiva em esteira motorizada. No grupo suplementado, os animais foram suplementados com OFT (1 g/kg) cinco vezes por semana por oito semanas. Método: Parâmetros contráteis como produção de força isométrica máxima (Tmax), velocidade máxima de contração (+dF/dt), velocidade máxima de relaxamento (-dF/dt), força tetânica máxima (Fmax) e resistência à fadiga foram analisados em músculos isolados. Resultados: Comparados ao grupo controle, os músculos EDL dos animais do grupo suplementado reduziram Tmax no primeiro (10.82 ± 0.89 vs 14.30 ± 0.67 mN/mm2. p < 0.01) e no segundo minutos de experimentação (9.85 ± 0.63 vs 13.12 ± 0.70 mN/mm2. p < 0.01), entretanto, aumentaram a resistência à fadiga (22.80 ± 0.97 vs 18.60 ± 0.51 segundos. p = 0.005). Conclusão: Nenhuma diferença foi observada no músculo sóleo.

Resumen Introducción: Los atletas profesionales y recreativos utilizan suplementos nutricionales diariamente para mejorar el rendimiento físico. Los ácidos grasos poliinsaturados (PUFA) se han utilizado en este sentido. Los n-3 PUFA, particularmente los ácidos eicosapentaenoicos (EPA) y el docosaexáenoico (DHA), se relacionan con importantes funciones fisiológicas y los beneficios de la suplementación se demuestran en diversas poblaciones. El aceite de hígado de tiburón (AHT) es fuente natural de n-3 PUFA. Objetivo: Evaluar el efecto de la suplementación con AHT en la contractilidad de músculos esqueléticos con diferentes características metabólicas, sololeo y extensor largo de dedos (EDL) de ratas sometidas a ocho semanas de entrenamiento intervalado de intensidad progresiva en estera motorizada. En el grupo suplementario, los animales fueron suplementados con AHT (1 g/kg) cinco veces por semana durante ocho semanas. Método: Parámetros contráctiles como producción de fuerza isométrica máxima (Tmax), velocidad máxima de contracción (+dF/dt), velocidad máxima de relajación (-dF/dt), fuerza tetánica máxima (Fmax) y resistencia a la fatiga se analizaron en músculos aislados. Resultados: En comparación con el grupo control, los músculos EDL de los animales del grupo suplementado redujeron Tmax en el primer (10.82 ± 0.89 vs 14.30 ± 0.67 mN/mm2. p < 0.01) y en el segundo minuto de experimentación (9.85 ± 0.63 vs 13.12 ± 0.70 mN/mm2. p < 0.01), sin embargo, aumentaron la resistencia a la fatiga (22.80 ± 0.97 vs 18.60 ± 0.51 segundos. p = 0.005). Conclusión: No se observó ninguna diferencia en el músculo sóleo.

Morphological description of ovary and uterus of the nurse shark (Ginglymostoma cirratum) caught off at the Fortaleza coast, Northeast Brazil / Descrição morfológica de ovário e útero de Tubarões-lixa (Ginglymostoma cirratum) capturados na costa de Fortaleza, Nordeste do Brasil

The nurse shark, Ginglymostoma cirratum (Bonnaterre, 1778) is one of the most studied species of elasmobranchs. However, the knowledge of their reproductive biology is still relatively rare, particularly in the western South Atlantic. This study aimed to describe the morphology of the uterus and the ovary of G. cirratum, based on specimens caught off at the Fortaleza/CE coast, northeast Brazil. Samples were collected from September 2012 to June 2013, from regular landings of artisanal fishing, which commercialize this species freely. A total of ten females were collected. The methodologies followed for analyzing the ovaries and uterus of those females included both macroscopic and histological analysis. G. cirratum has internal type ovary morphology, with invaginations of connective tissue, which defines compartments and separate oocyte groups in ovigerous lots. The epithelium lining the ovary changes from simple columnar ciliated in the area without ovigerous lots, which turns into a simple cubic epithelium in the coating portion of the epigonal organ where ovarian tissue is absent. The uterine mucosa has secretory cells denoted by Alcian Blue staining, indicating the production of mucopolysaccharides, even in immature individuals. This lecithotrophic shark has a uterine vascularized mucosa that is one characteristic of viviparous elasmobranch species.(AU)

O tubarão-lixa, Ginglymostoma cirratum (Bonnaterre, 1778) é uma das espécies mais estudadas de elasmobrânquios. O conhecimento de sua biologia reprodutiva, no entanto, ainda é relativamente raro, particularmente no Oeste do Atlântico Sul. Este estudo objetivou a descrição morfológica do útero e ovário de G. cirratum, baseado em espécimes capturados na costa de Fortaleza/CE, no Nordeste do Brasil. Um total de dez fêmeas foi coletado de setembro de 2012 a junho de 2013, nos desembarques regulares da pesca artesanal, que comercializam essa espécie livremente. A metodologia foi de acordo com as analises macroscópica e histológica dos ovários e útero. G. cirratum tem o tipo de morfologia de ovário interno, com invaginações de tecido conjuntivo, que define compartimentos e separa grupos de oócitos em lotes ovígeros. O epitélio que reveste o ovário varia de epitélio simples colunar ciliado na área que não apresenta lotes ovígeros para epitélio simples cúbico na porção de revestimento do órgão epigonal, onde o tecido ovariano é ausente. A mucosa uterina possui células secretoras, evidenciadas pela coloração em Alcian Blue, indicando a produção de mucopolissacarídeos, mesmo em indivíduos imaturos. Este tubarão lecitotrófico apresenta a mucosa uterina vascularizada, sendo esta uma característica de espécies de elasmobrânquios vivíparos.(AU)

Dientes fósiles de Carcharocles megalodon: la colección del Museo Universitario de Chieti (Italia). Parte I: análisis morfométrico / Fossil teeth of Carcharocles megalodon: the collection of the University Museum of Chieti (Italy). Part I: morphometric analysis

La especie extinta de tiburón Carcharocles megalodon (Clase: Chondrichthyes; Orden: Lamniformes) es considerado uno de los depredadores más grandes y más poderosos que ha poblado los mares templados de todo el mundo entre el Mioceno medio y el Plioceno (15,9-2,6 Ma). La reconstrucción de su historia evolutiva y ecología se basa principalmente en el estudio morfológico y métrico de los dientes, que representan la abrumadora mayoría de los restos fósiles de esta especie con esqueleto cartilaginoso hallados hasta hoy. En el presente artículo presentamos las características morfológicas y métricas de los dientes de Carcharocles megalodon que se conservan en el Museo Universitario de Chieti (Italia). La colección se compone de nueve dientes de la arcada superior, que pertenecerían a diferentes ejemplares de tamaño variable entre los 6,27-14,50 m y los 2.510-35.918 kg. de peso. Los dientes implementan el registro fósil existente de Carcharocles megalodon, de modo que los datos morfométricos recabados contribuirán a mejorar el conocimiento de los estudios filogenéticos y ecológicos de esta especie.

The extinct species of shark Carcharocles megalodon (Class: Chondrichthyes; Order: Lamniformes) is considered one of the largest and most powerful predators that populated the temperate seas around the world between the middle Miocene and the Pliocene periods (15.9-2.6 My). The reconstruction of its evolutionary history and ecology is based mainly on the morphological and metric studies of the teeth, which represent the overwhelming majority of the fossil remains of this cartilaginous skeleton species. In this article we present the morphological and metric characteristics of the teeth of Carcharocles megalodon that are housed in the University Museum of Chieti (Italy). In particular, the collection is composed of nine teeth of the upper arch, which belonged to different specimens of variable size and weight (total length range: 6.27-14.50 m; weight range: 2,510-35,918 kg). The teeth implement the existing fossil record of Carcharocles megalodon, so that the morphometric data collected will contribute to improve knowledge of the phylogenetic and ecological studies of this species.

Dientes fósiles de Carcharocles megalodon: la colección del Museo Universitario de Chieti (Italia). Parte II: análisis paleopatológico / Fossil teeth of Carcharocles megalodon: the collection of the University Museum of Chieti (Italy). Part II: paleopathological analysis

La paleopatología es la ciencia que estudia el origen y la evolución de las enfermedades del pasado. El interés por esta disciplina deriva del hecho de que la frecuencia y la distribución de las patologías que han afectado a las especies extintas se correlacionan con su ecología y etología. Esta suposición también es válida en el caso de Carcharocles megalodon, el tiburón más grande jamás existido, situado en lo alto de la cadena alimenticia y que vivió en los mares templados desde el Mioceno medio hasta el Plioceno (15,9-2,6 Ma). En el presente artículo presentamos las alteraciones patológicas de los dientes de Carcharocles megalodon que se conservan en el Museo Universitario de Chieti (Italia). La colección se compone de nueve dientes de la arcada superior, todos ellos con presencia de alteraciones patológicas correspondientes a defectos del desarrollo y traumas de la corona. Un diente en particular (espécimen #165), presenta una aposición anómala del esmalte sobre la superficie labial, que corresponde a una condición no descrita en la literatura. La colección del Museo Universitario de Chieti enriquece el registro paleopatológico relativamente pobre existente, contribuyendo a completar el conocimiento sobre la paleobiología de Carcharocles megalodon.

Paleopathology is the science that studies the origin and evolution of diseases. The interest in this discipline derives from the fact that the frequency and distribution of the pathologies that have affected the extinct species, correlate with their ecology and ethology. This assumption is also valid in the case of Carcharocles megalodon, the largest shark that ever existed, located at the top of the food chain and that lived in temperate seas from the middle Miocene to the Pliocene periods (15.9-2.6 My). In the present article we present the pathological alterations of the teeth of Carcharocles megalodon housed in the University Museum of Chieti (Italy). The collection consists of nine teeth of the upper arch, all of them with pathological alterations corresponding to developmental defects and crown trauma. A particular tooth (specimen #165) presents an anomalous apposition of the enamel on the labial surface, a condition not yet described in the literature. The collection of the University Museum of Chieti enriches the existing relatively poor paleopathological record, and could improve the knowledge of the paleobiology of Carcharocles megalodon.

A shark attack treated in a tertiary care centre: Case report and review of the literature

Although uncommon, shark attacks can lead to devastating outcomes for victims. Surgeons also face unique challenges during operative management such as exsanguination, shock, specific injury patterns and infections. This case report presents the management of a 39-year-old previously healthy female attacked by a shark while on vacation in Mexico. The patient sustained severe injuries to her left arm and her left thigh. She was transferred to a Canadian institution after ambiguous operative management in Mexico and presented with no clear antibiotic coverage and a Volkman's contracture of the left upper extremity. In total, the patient underwent four washouts of wounds, two split-thickness skin grafts, one free anterolateral thigh flap, and one free transverse rectus abdominus myocutaneous flap for the reconstruction and salvage of the left lower extremity. This article highlights the specifics of this case and describes important points in managing these devastating injuries.

Large-scale migration of a school shark, Galeorhinus galeus, in the Southwestern Atlantic

Knowledge of the spatial and temporal distribution patterns of chondrichthyans is critical for their effective management. In this study we report and analyze a large-scale latitudinal migration (~ 1,425 km) of a female school shark in the Southwestern Atlantic shelf where it is currently classified as Critically Endangered. During the austral summer (February 15, 2015), ninety-four school sharks were captured (75 females and 19 males) and tagged with fin tags in Nuevo Gulf (~ 42°43'S, 64°53'W, Argentina). A female of 112 cm total length was recaptured in Uruguayan shelf waters in the austral winter (August 17, 2015). This long displacement represents the first direct evidence to support Vooren and Lucifora's hypothesis of a single transnational population of Galeorhinus galeus in the Southwestern Atlantic. The good agreement found between the school shark habitat conditions (salinity 33-34, temperature 12-17°C) and the warmer member of Subantarctic Shelf Waters suggests that the seasonal variation in school shark abundance within this region could be related to water masses movements.(AU)

El conocimiento sobre los patrones de distribución espacio-temporal de los condrictios es crítico para su manejo efectivo. En este trabajo presentamos y analizamos una migración latitudinal de gran escala (~ 1.425 km) de una hembra de cazón en la plataforma del Océano Atlántico Sudoccidental, donde está actualmente clasificada como Críticamente en Peligro. Durante el verano austral (15 de Febrero de 2015), 94 cazones fueron capturados (75 hembras y 19 machos) y señalados con marcas "rotatag" en el Golfo Nuevo (~ 42°43'S, 64°53'W, Argentina). Una hembra de 112 cm de longitud total fue recapturada en aguas de la plataforma uruguaya durante el invierno austral (17 de Agosto de 2015). Este gran desplazamiento representa la primera evidencia directa para apoyar la hipótesis de Vooren y Lucifora sobre una única población transnacional de Galeorhinus galeus en el Océano Atlántico Sudoccidental. La gran coincidencia encontrada entre las condiciones de hábitat para el cazón (salinidad 33-34, temperatura 12-17° C) y el integrante más cálido del Agua de Plataforma Subantártica sugiere que la variación estacional en la abundancia del cazón dentro de esta región podría estar relacionada con el movimiento de las masas de agua.(AU)

Systematic Review of Heavy Metal Concentrations in Fish and Shellfish in Korea / 이화의대지

OBJECTIVES: Heavy metals ingested through the consumption of aquatic products can accumulate in the human body over the long-term and cause various health problems. This study aims to present comprehensive data on the amount of heavy metals found in fish and shellfish in Korea using a systematic review of studies that report on that issue. METHODS: The study used the following databases: PubMed, Korean Studies Information Service System, and Research Information Sharing Service. The search terms for PubMed included fish OR shellfish OR seafood AND mercury OR cadmium OR lead OR heavy metal AND Korea. The search terms for Korean Studies Information Service System and Research Information Sharing Service included eoryu sueun, eoryu kadeumyum, eoryu nab, eoryu jung-geumsog, paeryu sueun, paeryu kadeumyum, paeryu nab, paeryu jung-geumsog, eopaeryu sueun, eopaeryu kadeumyum, eopaeryu nab, and eopaeryu jung-geumsog. RESULTS: A total of 32 articles were selected for review. The total mercury, lead, and cadmium concentrations in fish and shellfish reported in each of the articles are summarized, as are the species of fish and shellfish with relatively high concentrations of heavy metals. Total mercury concentrations tended to be higher in predatory fish species, such as sharks, billfishes, and tuna, while lead and cadmium concentrations tended to be higher in shellfish. CONCLUSION: This paper is the first to report a comprehensive summary of the concentrations of heavy metals in fish and shellfish. This data could be used as evidence to protect Koreans from exposure to heavy metals due to the consumption of highly polluted aquatic products.

Early Devonian (Late Emsian) shark fin remains (Chondrichthyes) from the Paraná Basin, southern Brazil

ABSTRACT We report on the pioneering discovery of Devonian fish remains in the Paraná Basin, which represents the southernmost record of fishes from that period in mainland South America. The material comes from an outcrop at the lower portion of the São Domingos Formation, within Sequence C of the Paraná-Apucarana sub-basin in Tibagi, State of Paraná. Marine invertebrates are abundant in the same strata. The dark colored fish remains were collected in situ and represent natural moulds of partially articulated shark fin rays (radials). No elements such as teeth or prismatic cartilage have been preserved with the fins rays. This can be attributed to the dissolution of calcium-phosphatic minerals at the early stages of fossilization due to diagenetic processes possibly linked to strong negative taphonomic bias. This may have contributed to the fact that fishes remained elusive in the Devonian strata of this basin, despite substantial geological work done in the Paraná State in recent decades. In addition, the scarcity of fish fossils may be explained by the fact that the Devonian rock deposits in this basin originated in a vertebrate impoverished, cold marine environment of the Malvinokaffric Realm, as previously suspected.

Morphological study of the eye bulb of the hammerhead shark, Sphyrna lewini (Elasmobranch: Carcharhinidae) / Estudio morfológico del bulbo ocular del tiburón martillo, Sphyrna lewini (Elasmobranch: Carcharhinidae)

The hammerhead sharks shows a head laterally expanded with eyes and nostrils on the edges, which gives the species a hammer appearance. Another strand of studies indicates that the hypothesis of head shape alterations for better adaptions in the sensorial system with the development of structures associated to binocular sight and others sensorial organs. Given the variety of characteristics, the study aim was to describe the anatomical constitution of the hammerhead shark eye bulb. The bulb and its annexes exenteration was performed, and further dissection; the morphological description of the muscle insertions and eye bulb components were based on direct observation and were further photographed and catalogued. The eye bulb fragments and its annexes were histological technical. Between the sclera and the choroid it was possible to observe, by the electronical scanning microscopy, the thin layer called supra-choroid, in this region, spaces often filled by lymphatic vessels allied to a matrix formed by loose conjunctive tissue are found. In the choroid, a layer which is rich in blood vessels, loose conjunctive tissue and collagen fibers, was observed, besides pigmentary cells full of melanin in its interior, which result in its layer's dark color. Ciliary body is a choroid's dilatation; it has the aspect of a thick ring in finger-like shape, pigmented, covering the sclera surface and containing pigmentary cells. The crystalline capsule, which shows an acellular covering that, is hyaline and homogeneous. In the electronical scanning microscopy, it was observed that the capsule is extremely thick especially in the anterior face. The capsule is very elastic, constituted mainly by thin lamellae of collagenous fibers, as illustrated by the electronically scanning microscopy. Anatomic variations related mainly to the position of the eye bulb in the skull, fibrous tunica and lens call the attention and must be related to its habitat.

El tiburón martillo tiene la cabeza lateralmente expandida con los ojos y la nariz en sus márgenes. Estudios indican que alteraciones de la forma de la cabeza de estos animales son adaptaciones que mejoran el desarrollo del sistema sensorial y estructuras asociadas a la visión binocular y otros órganos sensoriales. Dada la variedad de características, el objetivo del estudio fue describir la constitución anatómica del bulbo ocular. Se disecó el bulbo ocular junto a sus anexos. La descripción morfológica de las inserciones musculares y componentes del bulbo ocular se basaron en la observación directa, siendo éstas fotografiadas y catalogadas. Entre la esclera y la coroides se observó através de microscopía electrónica de barrido, una delgada capa supra-coroides, y vasos linfáticos junto a la matriz formada por tejidos conectivos. La coroides, era abundante en vasos sanguíneos y fibras de tejido conectivo. Se observaron escasas células pigmentarias llenas de melanina, lo que se asemeja a un anillo en forma de dedo, de manera que cubren la superficie de la esclera y células que contienen pigmentos. En la cápsula del lente, fue posible observar un recubrimiento celular, hialino y homogéneo. En la microscopía electrónica de barrido, se observó una cápsula muy gruesa, principalmente en la región frontal. La cápsula elástica,estaba constituida por láminas delgadas, principalmente, por fibras de colágeno. Se concluyó que el bulbo ocular de estos animales posee variaciones anatómicas relacionadas, principalmente, con la posición del bulbo ocular en el cráneo, túnica fibrosa y lente, lo que puede estar directamente relacionado con su hábitat.

The associations between blood mercury levels and shark meat intake among workers in Gyeongsangbuk-do

BACKGROUND: Shark meat is used as sacrificial food in Gyeongsangbuk-do, and is a major source of dietary mercury. This study aimed to evaluate the effects of shark meat intake or the ritual of Jesa on blood mercury levels within workers living in Gyeongsangbuk-do. METHODS: This study was conducted from September 2016 to October 2016 in two cities of Gyeongsangbuk-do. To compare the differences between urban and rural areas, two workplaces each in Daegu as the urban area and Yeongcheon as the rural area were selected. General characteristics and characteristics related to shark meat consumption of the workers were acquired by personal interviews during their health examination. Blood mercury concentrations were analyzed by the gold amalgamation method using a direct mercury analyzer (DMA-80; Milestone Inc., Shelton, CT, USA). RESULTS: The shark consumption group had a higher blood mercury concentration than the non-consumption group. The levels of blood mercury increased with the frequency, annual intake, as well as most recent date of shark meat consumption. Moreover, the levels of mercury in blood increased according to the annual frequency of participation in Jesa (times per year) and the annual frequency of shark meat consumption during Jesa (times per year). CONCLUSIONS: Shark meat intake and the ritual of Jesa contributed to an increase in the blood mercury levels of workers in Gyeongsangbuk-do. Therefore, it is necessary to evaluate dietary exposure, occupational as well as other factors that may influence blood mercury concentrations in workers during their health examination, particularly in regions with high mercury exposures.

Bioecology and movements of bull sharks, Carcharhinus leucas, caught in a long-term longline survey off northeastern Brazil

A robust understanding of habitat usage by coastal shark species, and how it overlaps with human presence in densely-populated regions is needed to inform the development of efficient conservation strategies for these important top predators. An intensive longline survey conducted in nearshore waters off northeastern Brazil from 2004 through 2014 caught a total of 18 bull sharks (Carcharhinus leucas) (male-female ratio = 0.63:1), which can be dangerous to humans. Although most sharks were sexually mature, there was no evidence that this region could be used as a parturition or nursery area. Prey items identified in the guts of the sharks comprised teleosts, mollusks and elasmobranchs. Additionally, one satellite-tagged bull shark covered a great distance (> 3,000 km) in 75 days at liberty, making most use of shallow waters (< 20 m depth) and presumably also entering an estuarine area. Although bull sharks are not an important fishery resource in this region, such a reduced abundance coupled with its affinity for coastal and inshore habitats highlights the potential vulnerability of C. leucas to deleterious anthropic interferences off northeastern Brazil.(AU)

Um melhor entendimento sobre a utilização de hábitat das espécies de tubarões costeiros, e como ela se sobrepõe à presença humana em regiões altamente populosas, se faz necessário a fim de subsidiar o desenvolvimento de eficientes medidas de conservação para esses importantes predadores de topo. Um estudo intensivo utilizando espinhel, conduzido em águas costeiras do nordeste do Brasil entre os anos de 2004 e 2014, capturou um total de 18 tubarões cabeça-chata (Carcharhinus leucas) (proporção macho-fêmea = 0,63:1), os quais podem ser perigosos para humanos. Apesar da maioria dos tubarões estarem sexualmente maduros, não houve evidências de que essa região esteja sendo utilizada como uma área de parto ou berçário. Entre os itens alimentares identificados foram encontrados teleósteos, moluscos e elasmobrânquios. Além disso, um tubarão cabeça-chata marcado com um transmissor satélite percorreu uma grande distância (> 3.000 km) em 75 dias em liberdade, fazendo o uso de águas superficiais (< 20 m profundidade) e presumivelmente entrando em uma área estuarina. Apesar de os tubarões cabeça-chata não corresponderem a um recurso pesqueiro importante nessa região, tal reduzida abundância juntamente com a sua afinidade por hábitats costeiros reforçam a potencial vulnerabilidade de C. leucas às interferências antrópicas deletérias ao longo da costa nordeste do Brasil.(AU)